Suspension, Brakes and Tires Discussion, Abs, brake and traction control light in Item Specific Cadillac Discussion; New to forums and may not follow protocol. here goes. I have a 2003 SLS, 87000 miles. I replaced rear ...
New to forums and may not follow protocol. here goes. I have a 2003 SLS, 87000 miles. I replaced rear brakes several months ago. Soon thereafter, the ABS, brake and traction control light came on. When the ABS, brake and traction control lights are on, we can not change the temperature of the heat/cooling system or change where air comes out, rear heat/cooling controls do not work, seat heaters do not work, front and rear and the emergency brake will not release when shifted out of park. Dealership thought it was ABS module, replaced but did not fix. I asked them to remove it. This is very intermittent and i can not make it happen or make it stop. At times, the ABS and brake light will go out and the traction control stays on. When this happens we have full control. The dealership said to wait til it fails permanently before bringing back to them. About 3 months ago, I took the brakes off the left rear and disconnected the sensor on the hub and cleaned with contact cleaner. The car did not mess up for 2 and 1/2 months. It has now started again. At times, when the ABS light goes out, I can feel the ABS system maybe re-setting.Does anybody have ideas ??
Tell us what DTCs you see after a 10 mile test drive.
2; You are reporting mutiple unrelated symptoms. That is a red flag for me about how many "wireless" devices are you operating inside the car. RF interference is unpredictable.
3; Some of your symptoms could be caused by dirty-corroded primary power connections. Consider checking-cleaning the the battery cables and battery negative to chassis connection (under the rear seat bottom cushion).
I have a 2003 STS with the very same problems. My dealership can't locate the cause, other than to say that there might be a grounding problem. I have read many Cad forums and see that this problem is a very difficult one to solve.
My son in-law works for Bosch and used his Tech 2 to pull the codes and managed to isolate the communication link as a possible cause. All connectors and wires were continuity tested and checked ok. Wheel sensors tested ok. Battery connection cleaned and tested ok.
At one point during the testing routines the warning lights went out and all codes cleared ABS module tested ok. On engine restart the lights came on again. He returned to the last test location and retested. All wiring harnesses were jiggled and wiggled.
Automobile(s): 99STS,2004 Jeep Liberty Renegade,98 Deville RIP
Re: Abs, brake and traction control light
Oniram, do you remember which codes came up? The codes are a good way to narrow down the problem, use the method that JimD posted above and then come back with the current ones, as a guess only, the ABS unit you refer to is a combo pump and controller, and its ground does wear away, usually running a new ground wire from the pump to a different ground post should do the trick, but as I said, this is only a guess and a starting point. The unit is located on the bottom of the frame on the Drivers side near the front crossmember, a real nice place to put it.
Thanks for all the advice. I will try the battery cables Saturday. I drove the car yesterday and today. yesterday, the car was perfect, all lights off, no problems. I pulled it into the garage and parked. Got in it this morning, ABS, brake and traction control light on. No heat control, seat heaters etc. Lights did not go off for the 22 mile drive to work and back. Weird. What gets me, what can change when the car is sitting still? Is there a sensor on the wheels that interacts with the brakes somehow that can change or cool off? If there is a sensor, could I bypass it? To the person with the STS with similar issues, does this sound familiar to you?
Yes, that's how it started. Now the warning lights are on most of the time.
From what I gather from the experts, the fault is related to a bad ground.
I just got a copy of the GM ground locations diagram. We did manage to find the ground for the ABS system and it is working ok. I notice that the DIC was reporting a fault with the suspension system. So I am going to tackle that next. I'll post my finding here.
I have no control over the heater or AC when the lights are on. I did manage to wiggle the fan motor connector (on passenger side) got the fan to work for a while, but still could not control any setting.